A reader sent a link to this site and I thought it would be of interest to all of you. This site, produced by the National Park Service (NPS), has detailed maps showing the routing of various national historic trails. Of interest to California, it shows the National Old Trails Highway (US 66), El Camino Real (US 101 for the most part), Old Spanish Trail, and a few others. Come check it out!
Wow, this is awesome, thanks!